The project encompasses studies of three systems of distinct biochemical significance: lactose synthase, human serum transferrin and its cellular receptors and the enzymatic N-glycosylation of proteins. A connecting theme in the investigation is the identification of the molecular locations of the interaction sites on alpha-lactalbumin and galactosyltransferase, the two protein components of lactose synthase, and of the receptor interaction site of transferrin. Approaches will include differential kinetic labelling, covalent crosslinking with bifunctional reagents as well as the examination of fragments for inhibitory effects on the interactions. The relationship of structure and function in the individual proteins will also be investigated. Studies of protein N-glycosylation will focus on the use of peptide analogues containing modified glycosylation signal sequence as inhibitors and active site covalent labels.